I usually use ST3 with the 2 column layout, and since I develop in primarily C and C++, I thought it might be possible to force .cpp files to open on the left group and .h files on the right. XCode has this functionality (I think it is called Assistant) that ensures that when one file is opened or focused, its implementation/header is displayed in the opposite panel. I am aware of the Switch Header/Implementation feature, but this opens the file in the same group, requiring manual action to move the file to the opposite group.

Can this behavior be obtained with existing plugins, or is this even possible with the current API of Sublime Text?